Donald J. Hogan, 20
Hogan, whose parents adopted him when he was 5, always wanted to be a soldier. As a kid, every year on his birthday, he would ask for a toy gun. He was killed when a roadside bomb exploded near him while his unit was on foot patrol in southwest Afghanistan's Helmand province, on the Pakistani border. He was on his first tour in Iraq.
Sources: Times research, Defense Department, iCasualties.org